Discussion

Aortic valve atresia and an interrupted aortic arch is a rare congenital heart disease in which the survival of the patient depends on the blood supply to the ascending aorta and myocardium. Most of the time associated lesions provide an alternate source of blood supply to the brain and heart. Different reported sources of blood supply to the blind ascending aortic segment are (1) aorto-pulmonary (AP) window, (2) double aortic arch, (3) bilateral arterial ductus, and (4) aberrant right subclavian artery. ^{Reference Baker-Smith, Milazzo and Frush1–Reference Lacour-Gayet, Kandachar and Al-Bulushi3} When there are no above-mentioned sources of blood supply is available, it is through the circle of Willis, the blood flow to the brain and myocardium is maintained in a retrograde manner through carotids ascending aorta and then to the coronary arteries. ^{Reference Tannous, Moulick and Jonas4}

In the absence of an associated anomaly to perfuse the blind segment, type A interrupted aortic arch with aortic atresia is not compatible with life. However, in cases of type-A interruption and aortic atresia with aberrant right subclavian artery there could be minimal supply to the brain from the descending aorta through the aberrant right subclavian artery and right vertebral artery through circle of Willis. In type-B interruption and aortic atresia minimal supply to the brain and heart is by the left subclavian artery and left vertebral artery through circle of Willis. In above two situations, this blood supply might not be adequate to maintain both cerebral and myocardial perfusion. However, in type C interruption and aortic atresia, brain and coronary perfusion are supported by both the left carotid artery and left vertebral artery which in combination might provide adequate blood supply to the brain and myocardium and could be compatible with life. In the majority of the reported cases, perfusion to the brain and myocardium is provided by bilateral ductus, AP window or double arch. ^{Reference Lacour-Gayet, Kandachar and Al-Bulushi3} Only very few cases had no direct connection to the ascending aorta and all had an aberrant right subclavian artery. ^{Reference Careddu, Oppido and Ialonardi5} In our case, cerebral and coronary perfusion was maintained through a right-sided arterial ductus. Hence it was crucial to keep ductal patency with prostaglandin. Considering the high risk of a Damus–Kaye–Stensel operation with aortic arch repair, we decided to proceed with a hybrid procedure which includes placing stents in both the ducti and bilateral pulmonary artery banding.

Our report adds to the literature like the 3rd reported case of an interrupted aortic arch, aortic atresia with bilateral arterial ductus. Prompt identification of this disease is important to ensure survival by keeping ductal patency using prostaglandin. A hybrid procedure with bilateral ductal stenting and branch pulmonary artery banding is an alternative low-risk initial approach which can be considered if the surgical procedure is found to be high risk.